1. Field of the Invention
The invention is concerned with blends of glycerides and/or fatty acids, the use thereof in food applications and the preparation of such blends by partial enzyme hydrolysis.
2. Description of Related Art
Fats containing palmitoleic acid (=C16:1 fatty acid) are already known. In fact palmitoleic acid is a component in natural oils such as oils derived from macadamia nuts, which can contain up to 27 wt % of C16:1 fatty acid, but also oils like fish oil or seal blubber contain appreciable amounts of C16:1 fatty acid. As palmitoleic acid is considered to be a healthy oil component, that has health benefits such as antitumour activity (JP 59062523, Toyo Jozo Co Ltd), lowering serum cholesterol and LDL (Food Australia 1996, pp 216-222), and protective effect against ventricular arrhythmics as disclosed in U.S. Pat. No. 5,198,250 it would be highly appreciated if the fat containing the palmitoleic acid would be liquid at temperatures of 25xc2x0 C. or lower. This would ease its use in capsules for encapsulated food ingredients or food supplements. Moreover liquid forms of fat are easier to dose in food compostions than solid fats. However most of the readily available fats known to contain appreciable amounts of C16:1 are solid at room temperature or lower and thus not very suitable for above purposes.
Moreover the known fats containing appreciable amounts of C16:1 also contain appreciable amounts of other fatty acids such as c16:0 and C18:1. It would be very beneficial if we could make available fats that combine high levels of C16:1 with relatively low levels of C16:0 and C18:1. This would improve the performance, such as opacity, pourability, viscosity, dosing, and blending of these fats considerably. An attempt to achieve this is disclosed in JP -laid open 01/187 089 (Shikibo Ltd). Herein a process is given wherein an oil, in particular macademia oil is subjected to an enzymatic hydrolysis under conditions that result in complete hydrolysis, whereupon the fatty acids are collected in a fraction that is subjected to low temperature fractionation at about xe2x88x9220 to xe2x88x9225xc2x0 C. It is indicated that the starting material must be selected in such a way that a separation can be obtained between the C16:1 and the other fatty acids during the low temperature fractionation. This limits the choice of starting materials considerably. This accounts the more as macademia oil is a relatively rare and expensive oil. Further it would be very beneficial if the oil rich in C16:1 would also contain other healthy fatty acids, such as polyunsaturated fatty acids like EPA and DHA. We found eg that starting from a fish oil that contains more than 20 wt % C16:1, but also appreciable amounts of C16:0 and/or C18:1 it is very difficult to make an oil that contains simultaneously more than 20 wt % C16:1 and wherein the weight ratios C16:1 to C16:0 is more than 2 and the C16:1 to C18:1 weight ratio is more than 1.2 and that is essentially free of components such as cholesterol esters, normally present in fish oil under commercially acceptable process conditions. This can be attributed to the fact that during the low T-fractionation the separation of C16:0 and C18:1 from C16:1 is very difficult so that the oils resulting will have about the same weight ratios C16:1 to C16:0 and C16:1 to C18:1 as the starting material, unless very severe separation conditions are applied.
Therefore we studied whether we could develop a process that would result in a fat relatively rich in C16:1 and relatively lean in C16:0 and/or C18:1 and that would contain polyunsaturated fatty acids and that would be liquid at ambient temperature and lower. This study resulted in the finding of novel fat compositions that meet these aims and in a novel process to make such fat compositions.
Therefore our invention concerns in the first instance a blend of glycerides and /or fatty acids comprising:
i) 20-65 wt %, preferably 25-55 wt %, most preferably 30-45 wt % C16:1 fatty acid
ii) at least 2% (DHA plus EPA)
iii) balance other fatty acids with 12 to 24 C-atoms, including C16:0 and C18:1 while the C16:1/C16:0 weight ratio in the blend is greater than 2.0, preferably greater than 4.0 and its C16:1 to C18:1 weight ratio is more than 1.2, preferably more than 2 most preferably more than 2.5
DHA being the C22:6 polyunsaturated fatty acid and EPA being the C20:5 polyunsaturated fatty acid.
It was found that these blends have very beneficial product properties if the blend displayed an N10 (solid fat content measured by NMR pulse on non stabilised fat at 10 oC) of less than 10, preferably less than 8 most preferably less than 5. Because of this N-value these fats can be used beneficially in compounds wherein a liquid form of a fat is an advantage such as in food supplements. It was found that the best product properties were obtained if the blend contained a limited amount of C16:0 and C18:1 fatty acid, in particular when the amount of C18:1 ranged from 5-50 wt %, preferably 8 to 30 wt % the products performed very well.